marshmallow: simplified object serialization¶
Release v2.21.0. (Changelog)
marshmallow is an ORM/ODM/framework-agnostic library for converting complex datatypes, such as objects, to and from native Python datatypes.
from datetime import date
from marshmallow import Schema, fields, pprint
class ArtistSchema(Schema):
name = fields.Str()
class AlbumSchema(Schema):
title = fields.Str()
release_date = fields.Date()
artist = fields.Nested(ArtistSchema())
bowie = dict(name='David Bowie')
album = dict(artist=bowie, title='Hunky Dory', release_date=date(1971, 12, 17))
schema = AlbumSchema()
result = schema.dump(album)
pprint(result.data, indent=2)
# { 'artist': {'name': 'David Bowie'},
# 'release_date': '1971-12-17',
# 'title': 'Hunky Dory'}
In short, marshmallow schemas can be used to:
Validate input data.
Deserialize input data to app-level objects.
Serialize app-level objects to primitive Python types. The serialized objects can then be rendered to standard formats such as JSON for use in an HTTP API.
Get It Now¶
$ pip install -U marshmallow
Ready to get started? Go on to the Quickstart tutorial or check out some Examples.
Upgrading from an older version?¶
See the Upgrading to Newer Releases page for notes on getting your code up-to-date with the latest version.
Why another library?¶
See this document to learn about what makes marshmallow unique.
Guide¶
- Installation
- Quickstart
- Declaring Schemas
- Serializing Objects (“Dumping”)
- Deserializing Objects (“Loading”)
- Handling Collections of Objects
- Validation
- Specifying Attribute Names
- Specifying Deserialization Keys
- Specifying Serialization Keys
- Refactoring: Implicit Field Creation
- Ordering Output
- “Read-only” and “Write-only” Fields
- Next Steps
- Nesting Schemas
- Custom Fields
- Extending Schemas
- Examples